T/S Motor brake stopped working....help needed

[DougT]

I have a Sheppach 4000E table saw and the motor brake has stopped working. Can someone tell me what a possible cause can be or has anyone experienced the same problem?

Cheers

Doug

 

[Sawdust]

Count yourself luck - you can have a dado blade now :wink:

 

[jonny boy]

Hello Doug,
i'm not familiar with the scheppach motors but there is two types of possible brake designs, one is mechanically activated as the RPM's slow down and the other is an electronically activated brake which can be part of the starter switch, (these are usually on industrial three phase machines). If as I suspect, it's the mechanically operated one, this works by- on starting the motor, the centrifugal force causes a spring action opening of a device which is usually located behind the cooling fan at the end of the motor, it works by two soft washers pressing together when you stop the motor and it reduces to a specified speed. I may be mistaken but i'm certain it's this and it can be replaced. If you have the saw's manual and it has a diagram of the breakdown of parts, it should be there and have a part number. As I said earlier though, i'm faily sure it's this but someone who has more insight into this might put me straight.

good luck!
jonathan.

 

[DougT]

Thanks Jonathan for the reply, I will have a look at what you are suggesting.

Regards

Doug

 

[BradNaylor]

on starting the motor, the centrifugal force causes a spring action opening of a device

Sorry to be a pedant Jonathon, but there ain't such thing as 'centrifugal force'!

When something is spinning, it is the centrapedal force acting towards the centre of the circle that prevents the object flying off.

The tendancy for the object to fly off at a tangent to the circle is called the 'centrifugal effect'

Phew!!

Not bad for a guy who did his physics 'A'level 30 years ago this month!

Cheers
Dan

 

[dickm]

Sorry to be a pedant Jonathon, but there ain't such thing as 'centrifugal force'!
[snip]
Not bad for a guy who did his physics 'A'level 30 years ago this month!

Doesn't it depend on your "frame of reference"? (nearly 50 years since I did physics A-level, but been married to a very pedantic physicist for 42 of them)

 

[Sawdust]

on starting the motor, the centrifugal force causes a spring action opening of a device

Sorry to be a pedant ... it is the centrapedal force acting towards the centre of the circle that prevents the object flying off.

Cheers
Dan

The trouble with being a pedant is it draws people who are equally pedantic. It's 'centripetal': :wink: http://en.wikipedia.org/wiki/Centripetal_force

Mike

 

[Digit]

Once watched a demo of centripetal force in operation.
The aircraft banked around in a tight and continuous circle as the passenger lowered a bucket on a rope from the open door.
The bucket moved to the centre of the 'planes orbit and slowly descended, a bottle of champagne was placed in the bucket and then hauled back up into the aircraft!
Apparently the Ozzies used the system in the early days of their exploration of New Guinea.

Roy.

 

[Benchwayze]

Count yourself luck - you can have a dado blade now :wink:

And your saw won't shake itself apart, loosen the blade and send TCT teeth all over the workshop. I was lucky to be wearing a visor that day!

Brakes? Waste of space. Just switch off the darned saw and stand back till it stops. Then drop the guard down and unplug the bench until you need to use it again .

John